Toggle press



March 22, 1927.

N. w. DORMAN ET TOGGLE PRESS Filed 00 5 sheets-Sheet 1 glwua'nlfo vs March 22, 1927.

3 heets-$heet 2 Filed on. 24, 1925 N. W. DORMAN ET AL TOGGLE PRESS dmd Patented Mar. 22, 1927.

UNITED STATES PATENT 'OQFFVFICE.

NEAL w. DORMA-N AND MEREDITH R. HATCH, or TOLEDO, OHIO, ,AssIGNoRs To THE TOLEDO MACHINE AND TOOL COMPANY, OF TOLEDO, OHIO, n CORPORATION OF 1 OHIO.

TOGGI E PRESS.

Application filed October 24, 1925. Serial NO. 64,567.

This invention relates to drawing on toggle presses and particularly to the mechanism employed for communicating the req uisite movements and dwell to the blank holder from the customary crank shaft orother operating means. l I An object of our invention 1s. to produce an improved mechan sm of the above class which will permit a prolonged dwell or rest of the blank holder in work-blank holding position during the work drawing or forming-movements of the press plunger, thus enabling the performance of deep drawing or stamping, and materially enhancing the practicability and commercial value of presses of this character.

Another. object of the'invention is to produce a simple and improvedpress having the unique features of construction, operation and arrangement hereinafter more fully described. l

The invention is shown by way of illustration in the accompanying drawings, in which, Fig. *1 is bodying the invention with the lower portion broken away and with the blank holder and die carrying plunger in their upper most position; Fig. 2 is a vertical section on the line 2-2 in Fig. 1; Fig. 3 is a view similar to Fig. 2 showing both the blankholder and plunger in their lowermost positions; Fig. 4 is, a transverse section on the line H in Fig. 2 showing the sliding block and guideway; and Fig. "5 is a diagram indicating the length of dwell of the blank holder relative to the movement of, the plunger.

The illustrated embodiment of the invention comprises a pair of uprightsl and 2 having a support 3 therebetween for the female or matrix die and vertically reciprocable between and guided by thenprights 1 and 2 is a blank holder 4 which is adapted to be moved into position to engage the work and hold the same during the pressing or forming operation of the male die (not shown) which is carried by a plunger 5 re-' ciprocating in and guided by the blank or work-holder 4, as is well understood in the art.

The mechanism shown for reciprocating the die-carrying plunger 5 comprises a crank shaft 6 which has bearings at its opposite a front elevation of a press em end portions in the uprights l and 2, respectively, and fixed to each or either end of the crank-shaft is a gear 7 driven by a pinion 8' on a drive-shaft 8 the crankshaft 6 to obtain a more balanced action, it is to be understood that a single g Although it may be desirable to employ a gear 7 at each end of gear may be advantageously employed if desired.

The die-carrying plunger 5 is operated from the crank shaft 6 by a pitman 9, which may be formed in two sections connected together by a screw 1O rotatable in one section and in threaded engagement with the other section. Suitable mechanism is employed for turning the bolt 10 so that length adjustment of the pitman 9may be effected thereby moving the plunger 5.closer to or farther away from the work it being observed that the lower end of the arm 9 is pivoted to the plunger.

Extending across the upper portion of the frame, and hearing at its opposite ends in the uprights 1 and 2 is a rock-shaft 10 havof is a triangular-shaped lever member pro-* viding lever arms It and 15, the triangularshaped'lever member having equal sideswith an apex connected securely to the's haft,10.

Pivoted at one end toQthe 'arm 15 is a link 16, which is pivotally connected at its opposite end to a slide 17 movable in a guide 18. The guide 18 may constitute a part of the frame or may be connected thereto, and as shown, is disposed in angular positron with the upper end inclined inwardly toward the vertical plane of the rock-shaft 10 and with the lower end extending ,away from said plane. In the formshown, the guide 18 is inclined about 45 from a vertical plane pressing through the rock shaft 10. It is .to be understood that the position of this guide may be varied according to the operation desired.

Pivoted at one end to the arm 14 is a link 19, which is pivotall connected at its oppo: site end to a slidelock 2O movable in a guide 21. In this instance, the guide 211s positioned on the opposite side of the rockshaft to the guide 18 and is inclined at an angle of equal to angle of guide 18. It will be noted that the arm 19 is slightly curved to give clearance to the arm 15 when the rock shaft 10 is moved in a clockwise direction, as indicated in Fig. 2, while the guide 18 is provided with 'an opening t-hru which the link 16 may extend when in the position (Fig. 2).

In the operation of the mechanism so far described, rocking movement is imparted to the rock-shaft 10 from the crank shaft 6 by means of the links 13, and by movement of the rock-shaft 10 in a clockwise direction both the slide-blocks 17 and 20 are drawn upwardly in the guides 18 and 21 respectively. When the rock shaft 10 reverses its movements or turns in a counter clockwise direction, both slide-blocks 17 and 20 move downwardly and outwardly in their respective guides. In this manner it will be seen that a balanced action is obtained thru the positioning of the mechanism on opposite sides of the rock-shaft which is disposed centrally of the machine.

A pair of arms 22 and 23 project from the center of the respective shafts 22 and 23, and these are respectively connected to the lower ends of the slides 17 and 20 by links 24 and 2-1. Each rock-shaft 22, 23 has a pair of arms 25 and 25 projecting therefrom at each side of the respective arms 22* and 23 at approximately right angles thereto and these are connected by links 27 to mem hers 28.

From the above description it will be seen that clockwise movement of the rock-shaft 10 operates to raise or move the slides 17 and 20 upwardly, thereby tending to rotate the rock-shaft 22 in a counter-clockwise direction and the rock-shaft 23 in a clockwise direction. This opposite movementof the shafts 22 and 23 exerts, through the arms 25 and 25 respectively, an upward pull on the links 27, thereby raisin the blank-holder 4 away from the work. it will also be appar ent that movement of the rock-shaft 10 in a-f counter-clockwise direction operates through the connections described to rotate the rockshaft 22 in a clockwise direction and the rock-shaft 23 in a counter-clockwise direction, thus operating to move the blankholder downwardly or outwardly against the work to hold the latter in place as indicated in Fig. 3. v

It is desirable that the blank-holder 4 be.

moved into holding engagement with the work before the plunger 5 engages the work, and to maintain its blank-holding position until the plunger has been retracted. As indicated diagrammatically in Fig; 5, the line (1 indicates the operation of the blank-holder and the line 6 indicates the operation of the plunger. It will be seen from this diagram that the blank-holder 4.- is moved into work and does not release the work until the plunger has traversed a distance in its re tractmg movement.

It is apparentthat with the present blank holder operating means the blank holder 4, crank shaft 6 and rock shaft 10 are located in a common vertical plane which is parallel to the shafts; that the pair of rock shafts 22 and 23 are disposed at opposite sides of and at eciual distances from said plane, so that at al times the parts are in perfect balanced relation, which is an important feature in presses of this character, in order to cause a smooth running'and to prevent vibration and unnecessary strains in the machine. Upon a rocking of the shaft 10 the thrustand pulling forces communicated thereby to the rock shafts 22 and 23 are equal at all times and with respect to the center of the machine. \Vhile the machine is preferably provided with two side gears 7, from which power is communicated equally to each end of the rock shaft 10, it is apparent that only one of such gears may be employed and that the shaft 10 may be driven from only one end, as desired. It is preferable, however, for a perfect balanced action of the press and in order to prevent torsional strain on the shaft 10 that the arrangement be as indicated.

While the form of mechanism here shown and described is admirably adapted to fulfill the objections primarily stated, it is to be understood that it is not intended to confine the invention to the one form of embodiment herein disclosed, and it is susceptible of embodiment in various forms, all coming within the scope of the appended claims.

Whatwe claim as new and desire to secure by Letters Patent, is:

1. A press comprising a crank shaft, a blankholder, and means for operating said blank-holder, said means comprising rocking parts at each'side of the press turning on axes parallel to the crank shaft, toggles between said rocking parts and said blankholder, an oscillatory rocking part ,above and approximately coextensive with said crank shaft, connections between said first rocking parts and said oscillatory rocking part for transmitting movements from latter to.-the former, and an operative. connection between said crank shaft and oscillatory rocking part.

2. A press comprising a crank shaft, a blank-holder, and means for operating said blank-holder, said means comprising rocking parts at each side of the press turning on axes parallel to the crankshaft, toggles between said rocking parts and said blankholder, a second rocking part nearer the middle of the press and turning on an axis parallel to the crank shaft, said second rocking part being approximately coextensive with said crank shaft, connections between intermediate portions of said first and second rocking parts for transmitting movements fromthe latter to the former, and an operative connection between said crank' shaft and second rocking part.

3. A press comprising a crank shaft, a blank-holder, and means for operating said blank-holder, said means comprising rocking'parts at each side of the press turning on axes parallel to the crank shaft, toggles between said rocking parts and blanks holder, a second rocking part nearer the middle of the press, disposed above and turning on an axis parallel to said first rock ing parts and crank shaft, connections between intermediate portions of said first and second rocking parts for transmitting movemnt from the latter to the former, and operative driving connections between opposite end portions of said crank shaft and said second rocking part.

4. In a toggle press, a blank holder, a singl'e rock shaft disposed centrally above the blank-holder, a pair of rock shafts disposed below and at opposite sides of the single rock shaft, means for rocking the single rock shaft, means connecting the single rock shaft to each of said other rock shafts to impart predetermined rocking movements to the latter from the former, said means including reciprocatory movable members operating in inclined intersecting planes, and means connecting said lower rock shafts to the blank holder for imparting reciprocatory movements to the latter from rocking movements of the former.

5. In a toggle press, a frame, a plungeroperating crank shaft in said frame, a rock shaft above said crank shaft, an operative connection between said shafts, and blankholding mechanism operatively associated with said rock-shaft and including arms fixed to said rock-shaft, angularly disposed guides on opposite sides of said shaft, blocks slidable-in said guides, and a link connecting. each pair of blocks and arms respectively whereby rocking movements of said rock shaft'in one direction moves said blocks inwardly in saidrguides and movement in the opposite direction moves said blocks outwardly.

6. In a toggle press, a frame, a plungeroperating crank-shaft in said frame, a rocksh aft' operatively connected to said crankshaft, guides on opposite sides of and below said rock-shaft and disposed centrally of the machine, said guides being inclined inwardly toward said rock-shaft, arms fixed to said rock-shaft and extending oppositely therefrom, links pivoted to said arms,-

respectively, blocks slidable in said guides and connected to said links, rock shafts in said frame extending approximat'elyparallel to said first rock-shaft, arms fixed to said last rock-shaft and pivoted to said blocks, a blank-holder, and links connecting said arms to said blank-holder.

7. In a toggle press, a frame, a blankholder mounted for reciprocatory moveguides, links connected to said members respectively at one end and operatively connected to saidshaft at the other end, rockshafts extending crosswise of said frame below said guides, arfns fixed to said last rock-shafts, links connecting said arms and slidable members, and operative connections betweens said last rock-shaft and blank holder.

8. In a toggle press, a frame, a blankholder mounted for reciprocatory move ments in the frame, a rock shaft mounted in the frame crosswise thereof, means for operating said shaftand mechanism operatively connecting said shaft and blank holder including guides disposed below and on opposite sides of said shaft with their inner ends inclined inwardly, members slidable in said guides, and links pivoted at one end to said members and operatively connected at their opposite ends to said shaft whereby a rocking movement ofsaid shaft in one direction moves said members inwardly in said guides and movement in the opposite direction moves said members outwardly in said guides.

9. In a'toggle press, a frame, a blankholder mounted for vertical reciprocator movements in said frame, a rock-sha mounted in said frame crosswise thereof, means for operating said shaft, andoperative connections between said shaft and blank-holder including angularly disposed guides, members movable in said guides, and

means for connecting said members to said.

sha ft whereby oscillatory movement of said shaft in'one direction moves both members conjointly in one direction and movement of said shaft in the opposite directionmoves both members in the opposite direction.

'10. In a toggle press, a frame, a blankholder mounted for vertical 'recipro'catory movements in said frame, a plunger-operating crank-shaft mounted in said frame crosswise thereof, a rock-shaft above and extending substantially parallel to said crankshaft, an operative connection between said crank-shaft and rock-shaft, and mechanism for operatively connecting said rock-shaft to said blank-holder for imparting reciprocatory movements thereto, said mechanism includinga gair of angularly disposed arms fixed to sai rock-shaft, links pivoted respectively to said arms, blocks pivoted to.

- and said blocks, and connections between said last rock-shafts and blank-holder.

11. In a toggle press, a frame, a blankholder mounted for vertical reciprocatory movements in said frame, a plunger-operating crank-shaft disposed centrally of said frame, a rock-shaft in said frame parallel to and disposed approximately in the vertical plane of said crank shaft, a connection between said crank shaft and rock shaft, a rock-shaft on each side of said crank-shaftin parallel relation thereto and intermediate said first rock-shaft and crank shaft, guides in said frame adjacent said last rock shafts and inclined toward said first rock-shaft, members slidable in said guides, link connections between said members and first rock-shaft, connections between said members and saidlast rock-shafts whereby oscillation \of said first rock-shaft turns said second rock-shafts in opposite directions,

arms fixed to said second rock-shafts, and links connecting said arms and blankholder.

12. In a toggle press, a frame, a blankholder mounted for reciprocatory move.-

ments in said frame, a rock-shaft in said frame cross-wise thereof, means for operating said rock shaft, a double lever fixed to said shaft, angularly disposed guides on opposite sides of said lever, members movable in said guides, links connecting said,

members and lever whereby oscillatory movement of said rock-shaft in one direction moves both members inwardly said guides and movement thereof in the opposite direction moves both members outwardly in said guides, and mechanism for transmitting the movement of said members to said blank-holder thereby to lift the same when moved in one direction and lower the same when moved in the opposite direction.

13. In a toggle-press, a blank-holder, a pair of slide-members operable in divergent planes a stationary guide for each of said slide members, means for reciprocating the slide members in unison, and means connecting the slides to the blank-holder for imparting reciprocatory movements to the latter from the former.

14. In combination with the frame, a

NEAL Vs DORMAN. MEREDITH R. HATCH. 

